Nowadays it is typical, e.g. in respect of household waste, that households use as waste bags different bags, sacks or carrier bags, in which waste is placed. For example, in Finland it is normal to use plastic bags from shops, in which bags shopping has been brought home, as waste bags. The waste is carried in plastic carrier bags to the waste bin, into which typically the carrier bag, and its contents, closed with a knot is placed. The waste is transported onwards for further processing by a garbage truck. In modern systems one disadvantage, among others, is that the sorting of wastes is awkward. It is often possible that users do not bother to sort waste into its different components, but instead mix all waste in the same waste bag or waste bin. In this case mixed waste is produced, the reclamation of which is difficult.
Known in the art are solutions for sorting waste, in which solutions different types of waste are arranged to be transported in different containers, such as in waste bags or bins of different colors. For example, households place different types of waste in waste bags of different colors. A waste bag of a specific color is specified for each type of waste. Waste is transported e.g. in a normal garbage truck to a waste center, where the waste is sorted on the basis of the colors of the waste bags into different components. The sorting of waste optically is described in publication EP0759816. A drawback here is that there must be waste bags separately arranged for the purpose for each waste type to be sorted. Another drawback is also the uncertainty of operation of the automatic optical sorting apparatus used in sorting the waste bags in a dirty environment. The sorting of waste is described in publication WO03039773 A1. Also known in the art are solutions wherein wastes, more particularly waste bags, are provided with an RFID identifier and the wastes are taken to a sorting center or corresponding, in which is a sorting apparatus provided with a sensor that reads the information of the RFID identifier of the waste, more particularly of the waste bag. The information read by the sensor is transmitted to the sorting apparatus, which sorts the different waste components on the basis of the RFID identifier. This type of solution is presented e.g. in publication WO 2011/029991 A2. A method and means in handling waste is also known in the art from publication WO2010/112669 A1, wherein an RFID identifier and visual identifiers are arranged in the closing means of a waste bag, on the basis of the information provided by which identifiers the waste bags can, inter alia, be sorted into waste components.
One problem, among others, in prior art is that all waste bags are not necessarily provided with an identifier in the manner hoped for by the user, or the identifier has been damaged, in which case the sorting of waste in a waste station is made more difficult. In addition, some unsuitable material, e.g. metal, might have been mixed in amongst the different waste components, and this can be detrimental to the later use of the sorted material. In further processing, e.g. when incinerating waste, undesirable material, e.g. metal, can be mixed in amongst the waste to be incinerated, and this is detrimental to the functioning of the incineration process in a waste incineration plant.
In addition, the flexibility and adaptability of sorting in the solutions known in the art have sometimes been awkward.
The aim of the invention is to achieve a new type of solution in the sorting of wastes, by means of which the problems of prior art can be avoided.